Search PubMed⌕ Search

Biomedical subjects

M R Taylor

Publications and source records attributed to M R Taylor.

At least 19 recordsLinked to original sources

Use of the Internet by patients and their families to obtain genetics-related information.

OBJECTIVE: To characterize use of the Internet by patients and their families referred to general genetics clinics. PATIENTS AND METHODS: We developed a survey to assess Internet use among patients visiting urban and rural clinics in Colorado and Wyoming. One hundred eighty-nine surveys were distributed to patients and their family members visiting outpatient general genetics clinics in spring 2000. The 8-page anonymous survey instrument asked about use of the Internet to obtain genetics-related information (GRI). All participants were asked whether a physician or health professional had referred them to the Internet for GRI. Subjects who had previously used the Internet to search for GRI were asked to rate whether they considered the GRI they encountered to be accurate, inaccurate, easy to understand, confusing, or trustworthy. RESULTS: One hundred fifty-seven surveys (83%) were returned (52% urban; 48% rural). Ninety (60%) of 149 respondents were at the clinic for a new-patient visit, and 59 (40%) were follow-up visits. All respondents were older than 17 years; 141 (91%) of 155 respondents were the patient's parent or guardian. Seventy-three (47%) of 155 respondents had searched the Internet for GRI prior to their clinic visit. The patients and families themselves initiated the majority of such efforts; only 8 (5%) of 148 respondents had been referred to a site on the World Wide Web by a physician. Interestingly, 136 (92%) of 147 respondents indicated that they would be likely to visit a Web site that was recommended by a geneticist. The most compelling reasons for searching the Internet for GRI were to get information in layperson's terms (60/131 [46%]); to get information about treatment (16/131 [12%]); and to get information about genetic research (16/131 [12%]). Among respondents who reported visiting GRI Web sites, 24 (41%) of 58 agreed that information was confusing or difficult to understand, 35 (53%) of 66 agreed that information was accurate and trustworthy, and 44 (77%) of 57 agreed that using the Internet was a positive experience. CONCLUSION: Internet use among patients referred to general genetics clinics and their family members appears to be widespread. Respondents reported that they found some of the information confusing and questioned its accuracy. Referral to Web sites by physicians was reported rarely, although the majority of respondents said they would visit a Web site recommended by a genetics physician. Further studies are needed to establish the accuracy of Internet information and how best to integrate and/or accommodate the data into the genetics clinic.

Adult↗

Genetic testing for inherited breast and ovarian cancer syndromes: important concepts for the primary care physician.

The remarkable advances in the area of genetic testing are transforming the way clinical medicine is practised. In the case of the inherited breast-ovarian cancer syndrome the ability to engage in genetic testing of BRCA genes has raised novel issues over caring for patients who are at increased risk for these malignancies. The primary care physician is likely to play a pivotal role in identifying such persons. As only 10-15% of all breast cancers are caused by directly heritable mutations, cultivating the ability to identify those who may be at increased risk is an important skill for the primary care physician. Once it is established that an individual is at risk of BRCA mutation, the physician must understand the potential benefits and drawbacks of the various genetic BRCA tests. Taking such factors into account leads to the development of an appropriate plan for evaluation. Careful attention must also be paid to social and psychological issues that may affect patients and their families.

BRCA2 Protein↗

Current perspective new insights into the molecular basis of familial dilated cardiomyopathy.

Genetic disease transmission has been identified in a significant proportion of patients with dilated cardiomyopathy (DCM). Variable clinical characteristics and patterns of inheritance, as well as recent molecular genetic data, indicate the existence of several genes causing the disease. Several distinct subtypes of familial DCM have been identified. Autosomal dominant DCM is the most frequent form (56% of our cases), and several candidate disease loci have been identified by linkage analysis. Three disease genes are presently known: the cardiac actin gene, the desmin gene, and the lamin A/C gene. This latter gene has recently been found to be responsible for both the autosomal dominant form of DCM with subclinical skeletal muscle disease (7.7% of cases) and the familial form with conduction defects (2.6% of cases) or the autosomal dominant variant of Emery-Dreifuss muscular dystrophy. The autosomal recessive form of DCM accounts for 16% of cases and is characterized by a worse prognosis. An X-linked form of DCM (10% of cases) manifests in the adult population and is due to mutations in the dystrophin gene. In the rare infantile form of DCM, mutations in the G4.5 gene have been identified. Finally, some of the rare unclassifiable forms (7.7% of cases) may be due to mitochondrial DNA mutations. Clinical and experimental evidence based on animal models suggest that, in a large number of cases, DCMs are diseases of the cytoskeleton. However, other causes, such as alterations in regulatory elements and in signaling molecules, are possible. Moreover, other genes called modifier genes can influence the severity, penetrance, and expression of the disease, and they will be a main objective of future investigations. Familial DCM is frequent, cannot be predicted on a clinical or morphological basis and requires family screening for identification. The advances in the genetics of familial DCM can allow improved diagnosis, prevention and genetic counseling, and represent the basis for the development of new therapies.

Animals↗

The epidemiology of ocular toxocariasis.

Ocular toxocariasis damages vision and may cause blindness. It is a relatively 'new' disease, the histological changes having been described in 1950 and the causative organism identified in 1956. Many aspects of the epidemiology of toxocariasis are unclear. It is generally accepted that the usual route of entry to the eye is via the blood stream. Once the eye is invaded characteristic changes are produced with comparative sparing of the anterior segment. Species differences in susceptibility can be very marked. In Mongolian gerbils 55% of infected animals exhibit ocular lesions. Humans are fortunate in that they are far less susceptible to ocular infection. While it has been established that ocular toxocariasis is caused by Toxocara canis, the role of T. cati in this condition is still unclear. It is perhaps surprising that the prevalence of such a disease in humans should remain in doubt. However, the wide variation in the few estimates of prevalence may well be a reflection of the wide variation in exposure as evidenced by the wide variation in seroprevalence. A further factor mitigating against an identification of prevalence rates is the fact that the condition is usually unilateral. Most surveys of blindness stipulate a vision of 6/60 or less in the better eye and so toxocariasis cases go unrecorded. There is a need for surveys which identify the level of vision in both eyes.

Adolescent↗

Microscopic physical biomarkers in carbonate hot springs: implications in the search for life on Mars.

Physical evidence of life (physical biomarkers) from the deposits of carbonate hot springs were documented at the scale of microorganisms--submillimeter to submicrometer. The four moderate-temperature (57 to 72 degrees C), neutral pH springs reported on in this study, support diverse communities of bacteria adapted to specific physical and chemical conditions. Some of the microbes coexist with travertine deposits in endolithic communities. In other cases, the microbes are rapidly coated and destroyed by precipitates but leave distinctive mineral fabrics. Some microbes adapted to carbonate hot springs produce an extracellular polymeric substance which forms a three-dimensional matrix with living cells and cell remains, known as a biofilm. Silicon and iron oxides often coat the biofilm, leading to long-term preservation. Submicrometer mineralized spheres composed of calcium fluoride or silica are common in carbonate hot spring deposits. Sphere formation is biologically mediated, but the spheres themselves are apparently not fossils or microbes. Additionally, some microbes selectively weather mineral surfaces in distinctive patterns. Hot spring deposits have been cited as prime locations for exobiological exploration of Mars. The presence of preserved microscopic physical biomarkers at all four sites supports a strategy of searching for evidence of life in hot spring deposits on Mars.

Arkansas↗

A research strategy for investigating the ecological significance of endocrine disruption: report of a UK workshop.

In May 1997 the MRC Institute for Environment and Health hosted an expert, multidisciplinary workshop on the ecological effects of endocrine disruption, focusing on reproductive function, to identify research priorities. Particular objectives were to discuss the potential for effects at organisational levels higher than that of the individual (i.e. population, community and ecosystem levels), the range of taxa that may plausibly be susceptible, and our current knowledge of the environmental fate and behaviour of potential endocrine disrupters. The conclusions of this workshop are reported, with particular reference to a research strategy developed to ultimately address the significance of endocrine disruption at the level of the population. Specific research project areas considered to be of particular importance to the UK situation are also presented.

Animals↗

Ecological effects of endocrine disruption: current evidence and research priorities.

An overview is presented of the main evidence for endocrine disruption in wildlife, focusing on reproductive effects. While there are a few clear examples of endocrine disruptive effects resulting from environmental chemical exposure, in most cases a causal link between the observed abnormalities and chemical exposure has not been established. In other cases there appears to be a link but the specific chemicals responsible for the observed effects, and the mechanisms involved, remain to be elucidated. Also it is largely unknown whether or not observed changes in individual animals lead to population-level effects. Priority research projects for the UK, ultimately aimed at determining the population-level significance of endocrine disruption, are described.

Animals↗

Role of human-milk lactadherin in protection against symptomatic rotavirus infection.

BACKGROUND: Human milk contains a 46 kDa mucin-associated glycoprotein, lactadherin, which binds specifically to rotavirus and inhibits its replication. This study tested the hypothesis that lactadherin protects against symptoms of rotavirus infection. METHODS: 200 infants in Mexico City were recruited at birth and monitored by regular stool EIA for rotavirus, serology, and recording of feeding and stool patterns. Milk samples were obtained from the mothers weekly until 4 weeks post partum then monthly. The sample taken immediately before an infant's episode of rotavirus infection was assayed for lactadherin, butyrophilin, mucin, and secretory IgA. An infection was defined as symptomatic if diarrhoea occurred in the 5 days before or after detection of the virus. FINDINGS: 31 infants developed rotavirus infection; 15 were symptomatic and 16 had no symptoms. The median concentration of lactadherin in the milk samples (obtained 4-41 days [median 13] before the infection) was 48.4 (range 5.6-180) microg/mL in the asymptomatic group and 29-2 (6.2-103-4) microg/mL in the symptomatic group. Although these medians did not differ significantly, in logistic regression analysis adjusted for age at infection and secretory IgA concentration there was a significant difference between the groups (p=0O01). No association between symptom status and concentrations of butyrophilin, mucin, or secretory IgA was found. INTERPRETATION: Protection against rotavirus by human milk is associated with the glycoprotein lactadherin. This association is independent of products of the secretory immune system.

Adult↗

Direct monitoring of enzyme reactions using micellar electrokinetic capillary chromatography. Optimisation of drug glucuronide and sulfate conjugate hydrolysis.

This paper demonstrates the use of micellar electrokinetic capillary chromatography (MECC) to monitor enzyme reaction conditions. The hydrolysis reactions of model conjugated substrates (morphine and reduced flunixin glucuronides, napthyl sulfate), by proprietary beta-glucuronidase preparations, were studied under varied experimental conditions. Reactions were carried out in autosampler vials with incubation in a thermostatted CE autosampler tray. MECC was performed using borax buffer (17.5 mM, pH 9.3) modified with sodium dodecyl sulfate (70 mM). Repetitive injections were made from the sample vial throughout the course of the reactions at a frequency of up to 10 h-1. MECC provided a rapid and reproducible assay for the model substrates. Baseline interference from the enzymes prevented measurement of product increase, therefore substrate decrease was measured from the peak areas. Monitoring of reactions in this way has proved valuable in the optimisation of hydrolysis conditions used in sample preparation for drug analysis. beta-Glucuronidase preparations from Helix pomatia were found to give the best performance of those evaluated in terms of deconjugation efficiency.

Animals↗

Haematological reference ranges for schoolchildren.

There are few reports of reference ranges for haematological values in school age children and most studies extend over a small age range or have excluded a considerable proportion of the study population in an effort to omit those with haemoglobinopathies or anaemia. Blood samples from 2135 children aged 4-19 years, from randomly selected schools, were analysed by automated counter. Reference ranges for red cell, white cell and platelet indices are provided from the results. Median haemoglobin and red blood cell count values for girls and boys rose together with increasing age, up to 12 years, but then diverged. Girls had a higher platelet count than boys. Mean platelet volume rose with age and was inversely related to the platelet count. Plateletcrit fell with age but in girls there was a peri-pubertal peak. Total leucocyte count fell with age. The upper limits for total leucocyte count in this study are approximately 2 x 10(9) lower than those quoted in modern haematology textbooks. Lymphocyte, eosinophil and basophil counts fell with age with little difference between the sexes. Neutrophil and monocyte counts were similar for younger girls and boys but diverged in the older children with the older girls having higher values than boys.

Adolescent↗

Lactadherin (formerly BA46), a membrane-associated glycoprotein expressed in human milk and breast carcinomas, promotes Arg-Gly-Asp (RGD)-dependent cell adhesion.

Lactadherin, a major glycoprotein of the human milk fat globule membrane, is abundant in human breast milk and expressed in human breast carcinomas. Previously, we have shown that the mature protein, formerly known as BA46, has three domains: an epidermal growth factor (EGF)-like domain containing an Arg-Gly-Asp (RGD) cell adhesion sequence and C1 and C2 domains similar to those found in coagulation factors V and VIII. An alignment of lactadherin with its bovine (MGP57/53) and murine (MFG-E8) homologs shows that the RGD sequence has been conserved during evolution, suggesting that the RGD sequence is not fortuitous. We demonstrate that lactadherin purified using Triton X-114 phase partitioning promotes RGD-dependent cell attachment of green monkey kidney cells (MA104), mouse fibroblast cells (3T3-L1), and breast carcinoma cells (ELL-G). A lactadherin-specific monoclonal antibody, Mc3, inhibits attachment to purified lactadherin, suggesting that contaminants in the purification are not responsible for binding. In addition, the anti-integrin alpha(v)beta3 monoclonal antibody LM609 inhibits cell attachment of MA104 cells to lactadherin. These results demonstrate that lactadherin promotes RGD-dependent cell adhesion via integrins. Denaturation of lactadherin with heat and reducing conditions diminished cell attachment, suggesting that optimal cell attachment to RGD is dependent on the structural presentation of the sequence.

3T3 Cells↗

Community study of toxoplasma antibodies in urban and rural schoolchildren aged 4 to 18 years.

To estimate the prevalence of toxoplasma antibodies in schoolchildren and their association with clinical and environmental data, antibody titres were measured in 1276 children aged 4 to 18 years attending primary and secondary schools. Environmental and clinical data were obtained by questionnaire. Altogether 12.8% (163/1276) of children had antibodies to Toxoplasma gondii with no difference between the sexes. Seroprevalence was higher in country children (16.6% (50/302)) than town children (10.2% (75/737)). The proportion testing positive increased with age in both town and country children. No association with cat ownership was found. Toxoplasma seropositivity was associated with a positive toxocara titre, having had a bitch whelp in the past two years, and having an unwormed dog at home. Lack of energy or tiredness in the last 12 months were the only clinical features associated with a positive titre.

Adolescent↗

Serum concentrations of carboxyl-terminal propeptide of type I procollagen, amino-terminal propeptide of type III procollagen, cross-linked carboxyl-terminal telopeptide of type I collagen, and their interrelationships in schoolchildren.

We report pediatric age- and sex-specific 95% reference intervals for procollagen type I C-terminal propeptide (PICP), the cross-linked C-terminal telopeptide of type I collagen (ICTP), and procollagen type III N-terminal propeptide (P3NP), measured in plasma from 302 schoolchildren (156 boys, 146 girls) ages 4-19 years. All three markers displayed a significant variation with age (ANOVA P < or = 0.0015). PICP showed no detectable increase during adolescence for either sex, but decreased towards adult concentrations after the age of puberty, with an earlier decrease for girls than for boys (P < 0.01). ICTP and P3NP both increased in pubertal-aged children (P < 0.05), with an earlier increase in girls than in boys (P < 0.05), before decreasing towards adult concentrations (P < 0.01). All three collagen markers were highly correlated with one another (P < 0.001). The patterns observed mirrored the childhood growth curve and reflected the high turnover of bone and soft tissue during childhood growth.

Adolescent↗